A number of products using chemiluminescence have already been placed on the market. Generally, using such products, chemiluminescence is induced at a desired time by mixing a solution (fluorescent liquid) containing an oxalic acid ester and a fluorescent substance (dye) with a solution (oxidizing liquid) containing an oxidizing agent (generally hydrogen peroxide) and a catalyst component (e.g., a salicylate), and subjected to the purpose.
Such fluorescent and oxidizing liquids are produced using solvents for adjusting the concentration of the components and allowing reactive species in both liquids to mix uniformly and react with each other. For example, the Patent Document 1 discloses a fluorescent liquid in which an aromatic solvent such as a phthalic acid ester or a benzoic acid ester is used.
In recent years, however, it has been pointed out that such aromatic solvents have a problem with safety. In particular, phthalate solvents have been suspected of being environmental hormones, and therefore, there have been a movement to regulate them in Europe and other countries. Many children have many opportunities to use chemiluminescent materials as toys, and therefore, there has been a demand for highly safe fluorescent and oxidizing liquids for chemiluminescent materials using a non-aromatic solvent. The Patent Document 2 discloses that citric acid esters are used as a solvent for a fluorescent liquid or an oxidizing liquid using such a non-aromatic solvent.
On the other hand, in recent years, safe solvents have also been required for fire prevention. Conventionally, a solution produced by mixing acetyl tributyl citrate (ATBC), benzyl benzoate (BeB), and dipropylene glycol dimethyl ether (DMM) is frequently used as a solvent for fluorescent liquid composition. These solvents each have a high flash point, and a mixture of them also has a flash point of 100° C. or higher.
However, a conventional solution used as an oxidizing liquid exhibits a low flash point of about 20° C. to 40° C., because it contains an alcohol such as ethanol regardless of whether it is a phthalate or non-phthalate solution. Such an oxidizing liquid for a chemiluminescent composition has a low flash point, and therefore it is strictly handled as a dangerous material and has problems such as regulations applied to it in air cargo.